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Purpose: This study assessed the accuracy of linear measurements and dental implant selection performed in a smartphone application compared to a computer software. Materials and Methods: Forty-four DICOM files from the posterior mandible in partially edentulous patients were evaluated by three trained and calibrated examiners. Images were analyzed using three visualization methods: cross-sectional view (CScr) and coronal (CSco) plane using the CS 3D Imaging software, and coronal (DRco) plane using the DroidRender smartphone application. For standardization, bone width and height measurements were taken in the edentulous posterior mandible, 10 mm posterior to the mental foramen. Implants were selected according to the 2022/2023Straumann Standard implant catalog. Linear measurements were compared using repeated-measures ANOVA, and implant selection was compared using Friedman test. Statistical analysis was performed using SPSS software, with a significance level of 5%. Results: Linear measurements showed a statistically significant difference for bone width (P = .030), but not for height (P = .685). The choice of implant was not influenced by the visualization method (P = .614). Conclusions: It is possible to suggest the use of smartphone applications as an additional diagnostic tool for DICOM evaluation and implant planning in the posterior mandible. Smartphone applications allow an assessment not limited to 2D images or to static environments. Therefore, information exchange and diagnostic opinion in emergency situations may be facilitated. [ABSTRACT FROM AUTHOR]

Cone beam computed tomography (CBCT) is a widely available modality, but its clinical utility has been limited by low detail conspicuity and quantitative accuracy. Convenient post-reconstruction denoising is subject to back projected patterned residual, but joint denoise-reconstruction is typically computationally expensive and complex. In this study, we develop and evaluate a novel Metric-learning guided wavelet transform reconstruction (MEGATRON) approach to enhance image domain quality with projection-domain processing. Projection domain based processing has the benefit of being simple, efficient, and compatible with various reconstruction toolkit and vendor platforms. However, they also typically show inferior performance in the final reconstructed image, because the denoising goals in projection and image domains do not necessarily align. Motivated by these observations, this work aims to translate the demand for quality enhancement from the quantitative image domain to the more easily operable projection domain. Specifically, the proposed paradigm consists of a metric learning module and a denoising network module. Via metric learning, enhancement objectives on the wavelet encoded sinogram domain data are defined to reflect post-reconstruction image discrepancy. The denoising network maps measured cone-beam projection to its enhanced version, driven by the learnt objective. In doing so, the denoiser operates in the convenient sinogram to sinogram fashion but reflects improvement in reconstructed image as the final goal. Implementation-wise, metric learning was formalized as optimizing the weighted fitting of wavelet subbands, and a res-Unet, which is a Unet structure with residual blocks, was used for denoising. To access quantitative reference, cone-beam projections were simulated using the X-ray based Cancer Imaging Simulation Toolkit (XCIST). In both learning modules, a data set of 123 human thoraxes, which was from Open-Source Imaging Consortium (OSIC) Pulmonary Fibrosis Progression challenge, was used. Reconstructed CBCT thoracic images were compared against ground truth FB and performance was assessed in root mean square error (RMSE), peak signal-to-noise ratio (PSNR), and structural similarity index (SSIM). MEGATRON achieved RMSE in HU value, PSNR, and SSIM were 30.97 ± 4.25, 37.45 ± 1.78, and 93.23 ± 1.62, respectively. These values are on par with reported results from sophisticated physics-driven CBCT enhancement, demonstrating promise and utility of the proposed MEGATRON method. We have demonstrated that incorporating the proposed metric learning into sinogram denoising introduces awareness of reconstruction goal and improves final quantitative performance. The proposed approach is compatible with a wide range of denoiser network structures and reconstruction modules, to suit customized need or further improve performance.

We have grown and characterized (110)-oriented YBa2Cu3O7−x (YBCO)/PrBa2(Cu0.8Ga0.2)3O7−x (PBCGO) bilayer and YBCO/PBCGO/YBCO trilayer heterostructures, which were deposited by pulsed laser deposition technique for the nanofabrication of (110)-oriented YBCO-based superconductor (S)/insulator (I)/superconductor (S) tunneling vertical geometry Josephson junction and other superconductor electronic devices. The structural properties of these heterostructures, investigated through various x-ray diffraction techniques (profile, x-ray reflectivity, pole figure, and reciprocal mapping), showed (110)-oriented epitaxial growth with a preferred c-axis-in-plane direction for all layers of the heterostructures. The atomic force microscopy measurement on the top surface of the heterostructures showed crack-free and pinhole-free, compact surface morphology with about a few nanometer root mean square roughness over the 5 × 5 μm2 region. The electrical resistivity measurements on the (110)-direction of the heterostructures showed superconducting critical temperature (Tc) values above 77 K and a very small proximity effect due to the interfacial contact of the superconducting YBCO layers with the PBCGO insulating layer. Raman spectroscopy measurements on the heterostructures showed the softening of the Ag-type Raman modes associated with the apical oxygen O(4) and O(2)-O(3)-in-phase vibrations compared to the stand-alone (110)-oriented PBCGO due to the residual stress and additional two Raman modes at ∼600 and ∼285 cm−1 frequencies due to the disorder at the Cu–O chain site of the PBCGO. The growth process and structural, electrical transport, and Raman spectroscopy characterization of (110)-oriented YBCO/PBCGO bilayer and YBCO/PBCGO/YBCO trilayer heterostructures are discussed in detail. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the relationship between the structural parameters of trabecular bone obtained from CBCT imaging and the primary stability of dental implants. Materials and Methods: Sixty patients underwent implant placement followed by primary stability evaluation via measurement of the insertion torque (IT) and the implant stability quotient (ISQ). Gray values (GV) and the fractal dimension (FD) were also measured using pretreatment CBCT images. Results: FD values showed a positive and significant relationship with ISQ and IT values (P = .017 and P = .004, respectively). Additionally, there was a positive and significant correlation between GV and IT (P = .004) as well as between GV and ISQ (P = .010). FD and GV showed a considerable difference between the maxillary and mandibular jaws and were higher in the mandible. Only FD was significantly different between men and women and was higher in men. In the two age groups (older and younger than 45 years), only GV was considerably higher in people older than 45 (P < .05). Conclusions: Both fractal dimension and gray values obtained from CBCT are efficient methods for predicting the primary stability of the implant due to their relationship with ISQ and IT values. [ABSTRACT FROM AUTHOR]

In this position paper, the state of the art in immediate implant placement (IIP) at incisor-cuspid-premolar sites is described. The literature supports that the following prerequisites need to be simultaneously met for a predictable outcome: (1) there must be no acute infection; (2) there must be apical and palatal/lingual bone for implant anchorage; (3) the tooth must be inside the bone envelope; (4) the alveolar socket must have a favorable morphology (type I, IIa, IIb avoiding wide dehiscences); (5) there must be no midfacial recession; (6) the right implant must be selected; and (7) the surgeon needs to be experienced and skilled. A preoperative CBCT is required for IIP because multiple aforementioned prerequisites (2, 3, and 4) can only be assessed on the basis of 3D imaging. The final prerequisite relates to the importance of a perfect implant position, preferably leaving a horizontal gap of at least 2 mm between the implant shoulder and buccal bone wall. Guided surgery is preferred over free-hand surgery to accomplish this. Flapless surgery, socket grafting, connective tissue graft (CTG), and immediate provisionalization have been shown to contribute to hard and/or soft tissue stability. When the previously mentioned prerequisites are fulfilled, IIP may be considered over alternative treatment concepts (eg, early implant placement [EIP] and delayed implant placement [DIP]) based on time gain, minimal invasiveness, and similar outcomes in the literature. Given very strict selection criteria, clinicians should primarily screen patients for IIP before considering other treatment options with wider indications. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate via CBCT the anatomical variations of the maxillary teeth and associated major anatomical cavities, the maxillary sinus and nasal fossa. Material and Methods: CBCT scans of 221 patients were used to examine maxillary sinus variations, the posterior superior alveolar artery (PSAA) course, nasal septum variations, middle and inferior conchameatus variations, canalis sinuosus, infraorbital ethmoid cell, infraorbital canal, anterior nasal spina, and nasopalatine canal. Results: The incidence of anatomical variations was 32.6% for maxillary sinus septa, 50.9% for PSAA, 23.1% for nasal septum deviation, 6.3% for nasal septum spur and pneumatization, 3.6% for paradoxical middle concha, 14.9% for middle concha hypertrophy, 39.6% for middle concha bullosa, 0.45% for bifid inferior concha, 0.9% for paradoxical inferior concha, 60.1% for inferior conch hypertrophy, 1.8% for inferior concha bullosa, and 40.3% for the infraorbital ethmoid cell. The study mainly observed group 2 anterior nasal spina with a rate of 35.7%, group 1 nasopalatine canal with a rate of 37.1%, and infraorbital duct type 2 with a rate of 70%. In 20.4% and 47% of cases, canalis sinuosus was located in the right and left sides of the maxilla, respectively. Conclusions: Maxillary sinus variations, PSAA prevalence and localization, nasal septum and concha variations, anterior nasal spina subgroups, nasopalatine canal subgroups, canalis sinuosus prevalence, and localization and infraorbital ethmoid cell prevalence were found to be consistent with the literature. Moreover, a rare case of the lower bifid concha was identified. The nasomaxillary complex and related dental structures, which are a multidisciplinary study area, should be carefully examined in the presence of pain of unknown origin and the planning of surgical procedures. [ABSTRACT FROM AUTHOR]

Cone beam CT is integral to most modern radiotherapy treatments. The application of daily and repeat CBCT imaging can lead to high imaging doses over a large volume of tissue that extends beyond the treatment site. Hence, it is important to ensure exposures are optimised to keep doses as low as reasonably achievable, whilst ensuring images are suitable for the clinical task. This IPEM topical report presents the results of the first UK survey of dose indices in radiotherapy CBCT. Dose measurements, as defined by the cone beam dose index (CBDIw), were collected along with protocol information for seven treatment sites. Where a range of optimised protocols were available in a centre, a sample of patient data demonstrating the variation in protocol use were requested. Protocol CBDIw values were determined from the average dosimetry data for each type of linear accelerator, and median CBDIw and scan length were calculated for each treatment site at each centre. Median CBDIw values were compared and summary statistics derived that enable the setting of national dose reference levels (DRLs). A total of 63 UK radiotherapy centres contributed data. The proposed CBDIw DRLs are; prostate 20.6 mGy, gynaecological 20.8 mGy, breast 5.0 mGy, 3D-lung 6.0 mGy, 4D-lung 11.8 mGy, brain 3.5 mGy and head/neck 4.2 mGy. However, large differences between models of imaging system were noted. Where centres had pro-active optimisation strategies in place, such as sized based protocols with selection criteria, dose reductions on the 'average' patient were possible compared with vendor defaults. Optimisation of scan length was noted in some clinical sites, with Elekta users tending to fit different collimators for prostate imaging (relatively short) compared with gynaecological treatments (longest). This contrasts with most Varian users who apply the default scan length in most cases. [ABSTRACT FROM AUTHOR]

Cervical pedicle screws (CPS) provide biomechanically superior fixation compared to other techniques but are technically more demanding. Navigated CPS placement has been increasingly reported as a safe and accurate technique, yet there are few studies comparing different combinations of imaging and navigation systems under comparable conditions. With this study, we aimed to compare different imaging and navigation systems for CPS placement in terms of accuracy, screw placement time and applied radiation dose. For this experimental study, navigated CPS placement was performed at levels C2 to C7 in 24 identical radiopaque artificial spine models by two surgeons with different levels of experience using three different combinations of intraoperative 3D imaging devices and navigation systems. Accuracy, time and radiation dose were compared between the groups. In total, 288 screws were placed. Accuracy was > 98% in all groups with no significant differences between groups or between surgeons (P = 0.30 and P = 0.31, respectively), but the inexperienced surgeon required significantly more time (P < 0.001). Radiation dose was significantly higher with iCT compared to CBCT (P < 0.0001). Under experimental conditions, accuracy rates of > 98% were achieved for navigated CPS placement regardless of the imaging modality or navigation system used. Radiation doses were significantly lower for CBCT compared to iCT guidance. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the inter-fraction reproducibility and intra-fraction stability of breast radiotherapy using voluntary deep-inspiration breath hold (DIBH) and free breathing (FB) based on an optical surface imaging system (OSIS). Methods: Seventeen patients (510 breath-hold sessions) treated using a field-in-field (FiF) technique and twenty patients (600 breath-free sessions) treated with a volume-modulated arc therapy (VMAT) technique were included in this retrospective study. All the patients were positioned with the guidance of CBCT and OSIS, and also monitored with OSIS throughout the whole treatment session. Eight setup variations in three directions were extracted from the treatment reports of OSIS for all sessions and were subsequently manually introduced to treatment plans, resulting in a total of 296 perturbed plans. All perturbed plans were recalculated, and the dose volume histograms (DVH) for the target and organs at risk (OAR) were analyzed. Results: The OSIS and CBCT for both DIBH and FB treatments showed a good agreement of less than 0.30 cm in each direction. The intra-fraction respiratory motion data during DIBH were −0.06 ± 0.07 cm, 0.12 ± 0.15 cm, and 0.12 ± 0.12 cm in the lateral, longitudinal, and vertical directions, respectively; for FB, the respiratory motion data were −0.02 ± 0.12 cm, 0.08 ± 0.18 cm, and 0.14 ± 0.20 cm, respectively. For the target, DIBH plans were more sensitive to setup errors; the mean deviations in D95 for CTV were 39.78 Gy–40.17 Gy for DIBH and 38.46 Gy–40.52 Gy for FB, respectively. For the OARs, the mean deviations of V10, V20, and Dmean to the heart; V5, V20, and Dmean to the ipsilateral lung; and Dmean to the breast were lower for the FB plan compared with the DIBH plan. Conclusion: Based on OSIS, our results indicate that both DIBH and FB can provide good reproducibility in the inter-fractions and stability in the intra-fractions. When the patient respiratory motion is large, the FB technology has greater possibility for the undercoverage of the target volume, while DIBH technology is more likely to result in increases in dose to OARs (the lung, heart, and contralateral breast). [ABSTRACT FROM AUTHOR]

ABSTRACT Background Objective Methods Results Conclusions Condylar erosion (CE) may indicate an active progressive stage of temporomandibular joint osteoarthritis (TMJOA), but no studies have analysed the characteristics of this population.This cross‐sectional study analysed the characteristics of TMJOA patients with CE.A total of 267 patients were included. The severity of CE of all joints was evaluated using cone beam computed tomography (CBCT) and scored using a four‐point rating scale (0–III). Patients were categorised into mild (grade I), moderate (grade II) and severe (grade III) groups. Demographic and clinical characteristics were summarised and stratified by age and erosion severity. Univariate and multivariate logistic regression analyses were performed based on the assignment of the variables.The proportion of patients under 30 years old is much higher than other age groups. Compared to adults (≥ 20 years old), a higher proportion of adolescent patients (10–19 years old) choose orthodontics department for their first consultation (p < 0.01). And adolescent patients have a higher proportion of temporomandibular joint (TMJ) noise (p < 0.05) and a lower proportion of arthralgia (p < 0.001). Significant differences exist in CE severity between adolescents and adults (p < 0.001). The severe group had the youngest patients (p < 0.05) and the highest proportion of mandibular deviation and abnormal postural habits.Patients under 30 years of age constitute a significant proportion of TMJOA cases with CE. Compared to adults, adolescent patients have more severe CE and less arthralgia. Due to obvious dental and maxillofacial deformities and milder TMJ symptoms, adolescent patients may not be aware that they have TMJ disease, potentially leading to delayed treatment. [ABSTRACT FROM AUTHOR]

Objective: To assess the positional reproducibility of sedated and non-sedated pediatric tumor patients during radiotherapy through a retrospective analysis of cone-beam computed tomography (CBCT) and planned computed tomography (CT) scan data. Methods: The positional reproducibility of 40 pediatric tumor patients, aged 2 to 17 years with a median age of 4.5 years, who received radiotherapy under sedated and non-sedated states was retrospectively compared. The first CBCT images obtained during CT-based treatment planning were analyzed. The analysis encompassed six-dimensional positional changes, including vertical (Vrt), longitudinal (Lng), lateral (Lat), rotational (Rtn), pitch, and roll directions. Kolmogorov-Smirnov Z nonparametric rank-sum testing was employed to evaluate the positional deviations, considering absolute values regardless of directionality. Data were further stratified based on different fixation methods used during treatment. Results: Sedated patients exhibited significantly smaller positional deviations in Vrt, Lng, Lat, and Rtn directions in the body membrane group compared with their non-sedated counterparts (P<0.05). Similarly, sedated patients demonstrated reduced positional deviations in Vrt, Lng, Lat, Rtn, pitch and Roll directions in the head and neck group compared with non-sedated patients (P<0.05). Meanwhile, compared with vacuum bag plus body membrane fixation, the head and shoulder film fixation technique proved superior in terms of positional reproducibility during sedated treatment, specifically in Vrt, Lng, Lat, Pitch, and Roll directions (P<0.05). Similarly, compared with the alternative fixation method, the head and shoulder film fixation method showed better positional deviations in six-Dimensional directions in non-sedated patients (P<0.05). Conclusion: While sedated radiotherapy may offer advantages in terms of positional reproducibility, the present study underscores the importance of considering non-sedated radiotherapy as a viable option for pediatric tumor patients. Non-sedated treatment not only provides effective tumor control but also mitigates the psychological trauma and long-term side effects associated with repeated sedative drug use. Future studies should further explore the optimal sedation and fixation strategies for pediatric radiotherapy. [ABSTRACT FROM AUTHOR]

ABSTRACT Background/Aim Material and Methods Results Conclusions To evaluate the efficacy of the combined cone‐beam (CBCT)/3D‐replicas protocol on the clinical and radiographic outcomes of autotransplanted molars.Controlled clinical trial registered ISRCTN13563091 from August 2019 to September 2022. Patients aged 13–22 years requiring permanent premolar extraction and having at least one non‐erupted third molar were enrolled at the Institute of Stomatology, Stradins University, Riga, Latvia. Patients in the 3D‐replicas (n = 30) underwent maxillary CBCT scans and had 3D‐printed replicas of the third molar fabricated, while the control group (n = 28) did not. The clinical outcomes included tooth mobility, bleeding on probing, and periodontal pocket depth assessed at 3, 6, and 12 months. The radiographic outcomes included root development, obliteration, periapical status, and crown changes at 12 months.Of the 55 patients assigned to interventions, 46 completed the study. No significant differences in survival and radiographic outcomes were found between the control (n = 22) and 3D‐replica group (n = 24): root development (p = 0.3), root resorption (p = 0.057), periapical status (p = 0.7), and crown/root ratio change (p = 0.4). Logistic regression showed no significant associations between radiologic predictors (root resorption: p = 0.4; periapical status: p > 0.9; root development: p = 0.8). Significant clinical outcome predictors included total operative time (β = 0.0043, p = 0.049), Moorrees' stage (stage 4: β = −0.31, p < 0.001; stage 5: β = −0.39, p < 0.001), and four donor placement times (β = 0.93, p < 0.001), but group assignment was not a significant predictor.The CBCT/3D‐replica protocol showed no significant differences in the clinical or radiological outcomes. The high success rates in both groups suggest that the protocol is valuable primarily for optimizing surgical efficiency and as a training tool for clinicians. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Methods Results Conclusions Hormone replacement therapy (HRT) is a commonly used strategy for treating menopausal symptoms, while its relation with periodontitis remains unclear. This study aimed to explore the potential effects of HRT on periodontitis, mainly in aspects of bone loss and inflammation.The alveolar bone height (ABH), alveolar bone thickness (ABT), and bone mineral density (BMD) were measured in menopausal women with periodontitis who had received HRT or had not received HRT by cone beam computed tomography. Based on a rat model of periodontitis, the alveolar bone loss was evaluated by micro‐computed tomography and bone‐related biochemical markers. The expression/levels of inflammatory markers were measured to reflect periodontal inflammation.Although the differences were not all significant in each premolars/molars, the mesial/distal ABH and buccal/lingual ABT were lower, and the mesial/distal BMD was higher in patients in the HRT group than those in the control group. In a rat model of periodontitis, the alveolar bone loss was relieved by HRT. Additionally, HRT significantly weakened the elevation of inflammatory markers, including TNF‐α, IL‐1β, and IL‐6 in periodontitis rats.HRT contributes to the remission of periodontitis by inhibiting alveolar bone loss and inflammation. [ABSTRACT FROM AUTHOR]

Introduction: The esthetics of immediate implant dentistry can be challenging. Clinical considerations for immediate implant placement have demonstrated long‐term success rates comparable to traditional delayed implant protocols. However, it is a sensitive technique that requires proper treatment planning as well as meticulous execution to be predictable and successful in the long term. Methods: This clinical situation demands extensive knowledge of soft and hard tissue management for atraumatic tooth extraction followed by implant therapy, along with an understanding of the available materials to meet esthetic needs. This case report features a female patient with the chief complaint of needing to replace an anterior crown due to loss of retention. After a comprehensive oral assessment and cone beam computed tomography (CBCT) radiographic examination, it was determined that the crown on Tooth #9 was fractured at the subgingival level. Furthermore, gingival zenith positions displayed differences at the keratinized mucosa level in Teeth #7, #8, and #9, and the metal marginal areas of the porcelain‐fused‐to‐metal (PFM) crowns in the anterior area of Teeth #5, #7, #8, #9, and #10 were apparent. The procedure involved atraumatic extraction of Tooth #9, followed by immediate implant placement. Crowns on Teeth #5, #7, #8, and #10 were replaced, and veneers on Teeth #6 and #11 were fabricated using press lithium disilicate‐reinforced ceramic. Connective tissue graft (CTG) was contoured before final implant restorations. Results: The final implant crown was restored using a prefabricated abutment with a titanium base and lithium disilicate ceramic dental material. A well‐planned combined treatment, including atraumatic tooth extractions for immediate implants and ideal contouring of soft tissues, can significantly impact the outcome of esthetic restorations. Conclusions: Single immediate implant–supported crowns in the esthetic zone were able to fulfill the patient's esthetic expectations. [ABSTRACT FROM AUTHOR]

Aim Methodology Results Conclusions Despite the high success rate of endodontic microsurgery (EMS), it is difficult to suggest EMS as a general treatment option considering the difficulty of the procedure. A surgical guide has been proposed to overcome this problem. This study aimed to evaluate the stability of the surgical guide of a new design concept, as well as the accuracy of root resection, and to introduce the manufacturing method of the newly designed surgical guide.The experiment was conducted on 59 roots (9 in the maxillary and 50 in the mandibular region) of adult human cadavers. The surgical guide was designed using CAD/CAM design software based on cone‐beam computed tomography (CBCT) images and optical scan files. Unlike conventional surgical guides, the surgical guide proposed herein was designed to act as a tooth‐bone‐supported removable appliance. Two different types of guides were prepared: the osteotomy guide (O guide) for separation of the cortical bone above the root tip with a trephine bur with an outer diameter of 6 mm and the root resection guide (R guide) for resection of the root tip with a trephine bur with an outer diameter of 4 mm. For stability evaluation, the guides were pressed at five predetermined locations after installation and checked for the presence of any movement. For accuracy evaluation, the length at which the root tip was cut was measured and examined by overlapping the preoperative and postoperative CBCT images.Of the 15 R guides, 14 were stably installed without mobility. For the R guide group, the root tip was resected with an average of 3.2 mm, showing better results than the no‐guide group with an average of 4.0 mm.The newly designed surgical guide of this study can be applied more stably, enabling root resection to be performed more accurately and simply according to the preoperative plan than when performed without a guide. [ABSTRACT FROM AUTHOR]

Background: Fracture healing complications remain a major problem in trauma monitoring. An open wedge osteotomy of the distal radius provides a unique way of evaluating fracture healing. Since the introduction of cone-beam computed tomography (CBCT) at our institution, it has become the method of choice for assessing hand and wrist bones. To date, CT volumetry has been validated for multidetector CT (MDCT) but not for CBCT. Purpose: To assess osteotomy healing using CBCT volumetry and to evaluate two different segmentation techniques. Material and Methods: A total of 36 patients were surgically treated for malunited distal radius fractures with open-wedge osteotomy either leaving the void empty (open wedge empty [OWE]) or filled with bone graft substitutes (BGS). They were scanned using CBCT and MDCT postoperatively and after 3, 6, and 12 months. Segmentation was performed both manually and semi-automatically for volumetric measurement. Inter- and intra-observer reliability were assessed using intraclass correlation (ICC). Results: The median osteotomy volume in the OWE group postoperatively was 0.87 cm3 (range=0.42–2.72). At 3 months, all but one of the OWE volumes had diminished to half or less of their initial volume. In the BGS group, the median postoperative volume was 1.30 cm3 (range=0.73–1.81) and at 12 months, 76% of the initial volume remained. Reliability between CBCT and MDCT volumetry expressed as ICC was ≥0.96. ICC for the two segmentation techniques was ≥0.99 and ICC for inter-observer reliability ≥0.97. Conclusion: CBCT volumetry is a reliable tool and comparable to MDCT to quantify bone healing of an osteotomy. [ABSTRACT FROM AUTHOR]

Introduction: Several morphological alterations and remodelling occur in the mandibular condyle and glenoid fossa to adapt to trauma, malocclusion and other developmental disorders. Understanding these changes will aid healthcare providers in comprehending the pathophysiology of various Temporomandibular Joint (TMJ) problems. Aim: To evaluate the morphometric attributes of the condyle and glenoid fossa in the Gujarati population using Cone Beam Computed Tomography (CBCT). Materials and Methods: This cross-sectional radiographic morphometric investigation was conducted at the Department of Oral Medicine and Radiology at the College of Dental Sciences and Research Centre in Bopal, Gujarat, India using departmental archives from September 2019 to September 2022. A total of 40 CBCT scans (80 TMJs) were performed and analysed using the Papaya 3D and Genoray CBCT machines, along with Triana imaging software. Measurements were taken for condylar length, width, height, joint space (anterior, superior, posterior, medial, lateral) and the thickness of the Roof of the Glenoid Fossa (RGF) (sagittal, coronal) on the CBCT images. The aforementioned parameters were compared between genders, age groups and sides using a paired t-test and statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) software package (Chicago, IL, USA), version 21.0 for Microsoft (MS) Windows. Results: The mean age of the study participants was 34±9.6 years. The condylar width between males and females was the only condylar characteristic that differed significantly (p-value 0.001). Apart from the gender analysis, no statistically significant variations (p>0.05) were found in the thickness of the RGF when comparing age or side. However, in the gender-wise examination of joint space, males had significantly higher measurements of Superior Joint Space (SJS), Medial Joint Space (MJS) and Lateral Joint Space (LJS) than females. Conclusion: Gujarati males had a significantly larger condylar width compared to females. When considering gender-specific data, males also exhibited greater SJSs, MJSs and LJSs, as well as increased thickness of the RGF. The results of the present study may provide a relevant and comparable reference for the clinical assessment of individuals with healthy, functional, or pathological TMJs. [ABSTRACT FROM AUTHOR]

Introduction: Deep bite, a common orthodontic malocclusion, necessitates timely intervention to prevent potential side-effects. If left untreated, a deep bite can lead to increased tooth wear, dental injuries, and Temporomandibular Joint (TMJ) disorders. Various treatment modalities, such as anterior teeth intrusion and posterior teeth extrusion, are employed to correct deep bite. However, selecting the optimal approach requires careful consideration of patient-specific factors and treatment objectives. While anterior teeth intrusion is effective for mild to moderate cases, posterior teeth extrusion may be preferred in severe deep bite scenarios. There are various treatment modalities for deep bite correction such as intrusion arches and mini screw implants. Jayade's intrusion arch, detailed by A.V. Jayade in "Refined Begg for Modern Times" (2001), is an orthodontic appliance designed to correct vertical dental misalignments by intruding over-erupted anterior teeth. The modified three-piece intrusion arch is an advancement of the traditional intrusion arch technique. It incorporates three distinct segments: two lateral segments and a central segment. This design allows for greater precision and control over the intrusion forces applied to specific teeth or groups of teeth. Need of the Study: Simultaneous intrusion and retraction mechanics in orthodontic treatment are very challenging, and there is a paucity of data regarding the best modalities for achieving these with minimal root resorption. Introduction: Deep bite, a common orthodontic malocclusion, necessitates timely intervention to prevent potential side-effects. If left untreated, a deep bite can lead to increased tooth wear, dental injuries, and Temporomandibular Joint (TMJ) disorders. Various treatment modalities, such as anterior teeth intrusion and posterior teeth extrusion, are employed to correct deep bite. However, selecting the optimal approach requires careful consideration of patient-specific factors and treatment objectives. While anterior teeth intrusion is effective for mild to moderate cases, posterior teeth extrusion may be preferred in severe deep bite scenarios. There are various treatment modalities for deep bite correction such as intrusion arches and mini screw implants. Jayade's intrusion arch, detailed by A.V. Jayade in "Refined Begg for Modern Times" (2001), is an orthodontic appliance designed to correct vertical dental misalignments by intruding over-erupted anterior teeth. The modified three-piece intrusion arch is an advancement of the traditional intrusion arch technique. It incorporates three distinct segments: two lateral segments and a central segment. This design allows for greater precision and control over the intrusion forces applied to specific teeth or groups of teeth. Need of the Study: Simultaneous intrusion and retraction mechanics in orthodontic treatment are very challenging, and there is a paucity of data regarding the best modalities for achieving these with minimal root resorption. [ABSTRACT FROM AUTHOR]

Background: Recent advancements in dental implantology have significantly improved outcomes, with success rates of 90–95% over a 10-year period. Key improvements include enhanced preplanning processes, such as precise implant positioning, model selection, and optimal insertion depth. However, challenges remain, particularly in achieving correct spatial positioning and alignment of implants for optimal occlusion. These challenges are pronounced in patients with reduced bone substance or complex anthropometric features, where even minor misalignments can result in complications or defects. Methods: This paper introduces a vision-guided robotic system designed to improve spatial positioning accuracy during dental implant surgery. The system incorporates advanced force-feedback control to regulate the pressure applied to bone, minimizing the risk of bone damage. A preoperative CBCT scan, combined with real-time images from a robot-mounted camera, guides implant positioning. A personalized marker holder guide, developed from the initial CBCT scan, is used for patient–robot calibration. The robot-mounted camera provides continuous visual feedback of the oral cavity during surgery, enabling precise registration of the patient with the robotic system. Results: Initial experiments were conducted on a 3D-printed mandible using a personalized marker holder. Following successful patient–robot registration, the robotic system autonomously performed implant drilling. To evaluate the accuracy of the robotic-assisted procedure, further tests were conducted on 40 identical molds, followed by measurements of implant positioning. The results demonstrated improved positioning accuracy compared to the manual procedure. Conclusions: The vision-guided robotic system significantly enhances the spatial accuracy of dental implants compared to traditional manual methods. By integrating advanced force-feedback control and real-time visual guidance, the system addresses key challenges in implant positioning, particularly for patients with complex anatomical structures. These findings suggest that robotic-assisted implant surgery could offer a safer and more precise alternative to manual procedures, reducing the risk of implant misalignment and associated complications. [ABSTRACT FROM AUTHOR]

An image-quality CT phantom was scanned with three different 3D X-ray imaging guidance devices in the operating theatre: O-Arm, Loop-X, and Airo TruCT. Default acquisition and reconstruction parameters for lumbar spine procedures were used on each device. The tube current was set to a dose level of around 27 mGy. A task-based image quality assessment was performed by calculating the noise power spectrum (NPS) and task transfer function (TTF). A detectability index (d') was calculated for three simulated bone lesions. The noise magnitude of the O-Arm was higher than the Airo TruCT, and the Loop-X had higher noise than the Airo TruCT. The highest average NPS frequency was for the O-Arm images, and the lowest was for the Loop-X. The TTFs at 50% values were similar for the Airo TruCT and Loop-X devices. Compared to Airo TruCT, the TTF at 50% value increased with the O-Arm by 53.12% and 41.20% for the Teflon and Delrin inserts, respectively. Compared to Airo TruCT, the d' value was lower with Loop-X by −26.73%, −27.02%, and −23.95% for lytic lesions, sclerotic lesions, and high-density bone, respectively. Each 3D-imaging spine surgery guidance device has its own strengths and weaknesses in terms of image quality. Cone-beam CT systems apparently offer the best compromise between noise and spatial resolution for spine surgery. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study is to assess accuracy, time‐efficiency and consistency of a novel artificial intelligence (AI)‐driven automated tool for cone‐beam computed tomography (CBCT) and intraoral scan (IOS) registration compared with manual and semi‐automated approaches. Materials and Methods: A dataset of 31 intraoral scans (IOSs) and CBCT scans was used to validate automated IOS‐CBCT registration (AR) when compared with manual (MR) and semi‐automated registration (SR). CBCT scans were conducted by placing cotton rolls between the cheeks and teeth to facilitate gingival delineation. The time taken to perform multimodal registration was recorded in seconds. A qualitative analysis was carried out to assess the correspondence between hard and soft tissue anatomy on IOS and CBCT. In addition, a quantitative analysis was conducted by measuring median surface deviation (MSD) and root mean square (RMS) differences between registered IOSs. Results: AR was the most time‐efficient, taking 51.4 ± 17.2 s, compared with MR (840 ± 168.9 s) and SR approaches (274.7 ± 100.7 s). Both AR and SR resulted in significantly higher qualitative scores, favoring perfect IOS‐CBCT registration, compared with MR (p =.001). Additionally, AR demonstrated significantly superior quantitative performance compared with SR, as indicated by low MSD (0.04 ± 0.07 mm) and RMS (0.19 ± 0.31 mm). In contrast, MR exhibited a significantly higher discrepancy compared with both AR (MSD = 0.13 ± 0.20 mm; RMS = 0.32 ± 0.14 mm) and SR (MSD = 0.11 ± 0.15 mm; RMS = 0.40 ± 0.30 mm). Conclusions: The novel AI‐driven method provided an accurate, time‐efficient, and consistent multimodal IOS‐CBCT registration, encompassing both soft and hard tissues. This approach stands as a valuable alternative to manual and semi‐automated registration approaches in the presurgical implant planning workflow. [ABSTRACT FROM AUTHOR]

Objective: To compare bone volume and height changes of two types of deproteinized bovine bone mineral (DBBM) for lateral window sinus floor elevation (LSFE) with simultaneous implant placement. Materials and Methods: This retrospective cohort study involved 72 patients who underwent LSFE using low‐temperature sintered cancellous bone‐derived DBBM (C‐DBBM) or high‐temperature two‐step sintered epiphyseal‐derived DBBM (E‐DBBM). Cone‐beam computed tomography (CBCT) was acquired preoperatively, immediately postoperatively, 6 months and 1–4 years post‐surgery. Bone volume (BV), apical bone height (ABH), endo‐sinus bone gain (ESBG), and crestal bone level (CBL) were evaluated through three‐dimensional fitting and superimposition. Linear mixed models (LMM) were employed to analyze factors influencing the reduction of BV (ΔBV) and ESBG (ΔESBG). Results: The E‐DBBM group showed no significant change in BV 1–4 years post‐surgery, while the C‐DBBM group demonstrated a significant reduction (p =.006) with volume stability of 85.86%. Bone height in the E‐DBBM group increased at 6 months and subsequently decreased at 1–4 years (p =.003). In the C‐DBBM group, it decreased at 6 months (p =.014), then further decreased at 1–4 years (p =.001). ΔESBG was lower in the E‐DBBM group than the C‐DBBM group from immediate postoperative to 1–4 years (p =.009). LMM showed graft material type was the primary factor influencing ΔBV (p =.026) and ΔESBG (p =.003). Conclusions: Within the limitations of this study, both types of DBBM could achieve favorable clinical outcomes. E‐DBBM demonstrated enhanced stability in maintaining bone volume and height. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the influence of multiplanar reconstruction thickness on the detection of peri‐implant bone defects with a standalone zirconia implant and compare it to when another implant is in the vicinity using cone‐beam computed tomography (CBCT). Materials and Methods: Five dry human mandibles were used to create twenty implant sites in the second premolar and first molar regions. The OP300 Maxio was used to acquire CBCT images (90 kVp, 6.3 mA, 5 × 5 cm FOV, and 0.125 mm3 voxel size) before and after creating 3 mm peri‐implant bone defects in the buccal aspect of the premolar region. Half of the scans featured a single zirconia implant in the premolar region, while the others had two implants in the premolar and molar regions. Three reconstruction thicknesses (0.125 mm, 1 mm, and 2 mm) were considered for the multiplanar reconstruction analyses. Five oral and maxillofacial radiologists assessed the detection of peri‐implant bone defects using a 5‐point scale. Diagnostic parameters were calculated and compared using Two‐way ANOVA (α =.05). Results: The studied factors showed no significant influence on the diagnosis of peri‐implant bone defects (p >.05). Diagnostic performance was notably higher with a single implant, especially with a 2‐mm reconstruction thickness (AUC = 0.88, sensitivity = 0.68, specificity = 0.94). Although the differences were not statistically significant, the results were more modest when two implants were present (AUC = 0.80, sensitivity = 0.58, specificity = 0.82). Conclusions: The presence of an adjacent zirconia implant and variations in reconstruction thickness did not influence the detection of 3 mm buccal peri‐implant bone defects on CBCT images. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the performance of low‐dose cone beam computed tomography (CBCT) protocols with regard to linear bone measurements in the posterior mandible for implant planning compared with higher dose protocols. Materials and Methods: Forty‐two edentulous posterior sites in human cadaveric mandibles were imaged in three CBCT scanners using three or four protocols with varying exposure parameters to achieve lower dose. Co‐registration was performed to generate sagittal and cross‐sectional image sections representative of the implant site. Three observers measured bone height, from the alveolar crest to the mandibular canal, and width, three mm from the top of the alveolar crest. Intra‐ and interobserver reproducibility were assessed for the cases rated as nonmeasurable as well as for completed measurements. The measurements were analyzed using paired t‐tests for differences among the CBCT protocols and the frequency distribution of nonmeasurable cases with a Pearson Chi‐square test. Results: Reproducibility for registering nonmeasurable cases varied among observers; however, no consistent significant differences were found in the frequency distribution of these cases among observers, units, and protocols. Intraclass correlation coefficients (ICC) were >0.9 for all measurements of bone height and width. Mean differences of <0.5 mm were found regardless of protocol; however, one observer did in some cases produce larger differences. Conclusion: Linear bone measurements did not differ significantly and could be performed with excellent reliability, using low‐dose CBCT protocols compared with standard and high‐resolution ones. Varying approaches for rating nonmeasurable cases were found, indicating differences in diagnostic strategies related to implant planning among observers. [ABSTRACT FROM AUTHOR]

Objective: To assess the relative position of mini‐implants to retain a mandibular overdenture, according to the surgical protocol, technical and anatomical factors. Methods: Mandibular cone‐beam computed tomography (CBCT) scans were analyzed for 73 patients who received four one‐piece titanium‐zirconium mini‐implants. Drilling was performed using a 1.6 mm needle drill and a 2.2 mm Pilot Drill, according to the bone density with a surgical stent. Post‐insertion CBCT images in DICOM format were analyzed using the E‐Vol‐DX software with BAR filters. Divergence angle between implants and between implants and the overdenture path of insertion was measured using CliniView 10.2.6 software. Results: Divergence between implants ranged from 0° to 22.3° (mean = 4.2; SD = 3.7) in the lateral and from 0° to 26.2° (mean = 5.3; SD = 4.1) in the frontal projections (p <.001). Only 1 (0.2%) and 3 (0.7%) of the measurements were higher than 20° in the lateral and frontal views, respectively. The mean angulations between the implant and the path of insertion for the overdenture were 9.3° (SD = 7.5) and 4.0° (SD = 2.9) for the lateral and frontal views, respectively (p <.001). Regression analyses showed a significant association between the divergence of implants and the frontal view projection (p <.001), greater distance between the paired implants (p =.017), the flapped surgical protocol (p =.002), higher final insertion torque (p =.011), and deeper preparation with the needle drill (p <.001). Conclusions: The mini‐implants were placed with low divergence angles and satisfactory parallelism. Factors including shorter distances between the implants, higher density bone, and a flapless surgical approach all contributed positively to improved parallelism of the mini‐implants. [ABSTRACT FROM AUTHOR]

Objectives: To investigate long‐term alveolar ridge bone changes in patients treated with the split‐crest technique (SCT) with simultaneous implant placement. Materials and Methods: Alveolar ridge width (ARW) was measured with a caliper immediately before (ARW1) and after SCT (ARW2) with a caliper. Existing CBCT scans taken at least 5 years postoperatively were used to assess the healed ARW (ARWF), buccal bone thickness (BBT), and lingual/palatal bone thickness (L/PBT) at 0, 3, and 5 mm apically from implant platform level (IPL). The distance between IPL and buccal bone crest (IPL‐BBC) was also measured. Findings were compared with Wilcoxon and Student's t tests (p <.05). Results: Records of thirty patients with 85 implants were included. Eleven patients (31 implants) presented CBCT scans taken in two separate occasions, resulting in 116 measurements. Tomographic follow‐up ranged from 5 to 18 years (11.5 ± 4.18 years). Mean ARW increased from 3.2 ± 0.6 to 6.6 ± 0.48 mm after SCT, but significantly reduced overtime to 4.46 ± 0.83 mm (ARWF) (p <.0001). Mean BBT was 0.5 ± 0.9, 1.3 ± 0.9, and 2.0 ± 1.2 mm, while mean L/PBT was 0.9 ± 0.7, 1.6 ± 0.9, and 2.1 ± 1.0 mm at 0, 3, and 5 mm from IPL, respectively. IPL‐BBC distance varied up to 8.7 mm (1.4 ± 2.0 mm), with 56/116 measurements (51/85 implants) showing IPL‐BBC = 0 mm. Conclusion: Although SCT with simultaneous implant placement can predictably increase ARW postoperatively, ARW tended to significantly reduce over time, due to reductions in BBT and L/PBT, especially coronally. Nonetheless, 60% of the implants still presented some buccal bone at IPL. [ABSTRACT FROM AUTHOR]

Background: Fluoroscopy-guided PTNB for fluoroscopy-identifiable lung lesions has been suggested as a useful method for the pathological diagnosis of lung lesions; however, it is lacking in accuracy and safety compared to CT-guided PTNB. Thus, we aimed to investigate the diagnostic accuracy and complications of fluoroscopy-guided percutaneous transthoracic needle biopsy (PTNB) with the aid of pre-procedural planning cone-beam computed tomography (CBCT) in order to take advantage of their respective strengths. Methods: A total of 255 fluoroscopy-guided PTNBs with the aid of planning CBCT were performed. Pre-procedural planning CBCT was conducted to calculate the shortest length from the skin puncture site to the margin of the target lesion for the needle trajectory. No intra-procedural CBCT was performed. The diagnostic performance of fluoroscopy-guided PTNB with the aid of planning CBCT was calculated. The prognostic factors for diagnostic failures and complications were evaluated using logistic regression analysis. Results: The accuracy, sensitivity, specificity, PPV, and NPV were 97.3%, 88.0%, 90.9%, 100%, and 62.5%, respectively. There were 29 diagnostic failures (11.8%), and the multivariable analysis showed that a longer lesion depth on CBCT and a shorter specimen length were each associated with diagnostic failure (p = 0.010 and 0.012, respectively). Complications occurred in 34 PTNBs (13.3%). The multivariable analysis showed that an increased total number of biopsies per lesion, a longer length of lung aeration via needle insertion, a smaller lesion size on CT imaging (≤20 mm), and the presence of an air bronchogram were associated with the occurrence of complications (p = 0.027, <0.001, 0.003, and 0.020, respectively). Conclusions: Excellent diagnostic accuracy was obtained by fluoroscopy-guided PTNB with the aid of planning CBCT. Compared to that of CT- or CBCT-guided PTNB, the procedure-related complication rate was acceptably low, but the radiation dose to patients could be potentially reduced. [ABSTRACT FROM AUTHOR]

Background/Objectives: To assess the impact of a vendor-agnostic deep learning model (DLM) on image quality parameters and noise reduction in dental cone-beam computed tomography (CBCT) reconstructions. Methods: This retrospective study was conducted on CBCT scans of 93 patients (41 males and 52 females, mean age 41.2 years, SD 15.8 years) from a single center using the inclusion criteria of standard radiation dose protocol images. Objective and subjective image quality was assessed in three predefined landmarks through contrast-to-noise ratio (CNR) measurements and visual assessment using a 5-point scale by three experienced readers. The inter-reader reliability and repeatability were calculated. Results: Eighty patients (30 males and 50 females; mean age 41.5 years, SD 15.94 years) were included in this study. The CNR in DLM reconstructions was significantly greater than in native reconstructions, and the mean CNR in regions of interest 1-3 (ROI1-3) in DLM images was 11.12 ± 9.29, while in the case of native reconstructions, it was 7.64 ± 4.33 (p < 0.001). The noise level in native reconstructions was significantly higher than in the DLM reconstructions, and the mean noise level in ROI1-3 in native images was 45.83 ± 25.89, while in the case of DLM reconstructions, it was 35.61 ± 24.28 (p < 0.05). Subjective image quality assessment revealed no statistically significant differences between native and DLM reconstructions. Conclusions: The use of deep learning-based image reconstruction algorithms for CBCT imaging of the oral cavity can improve image quality by enhancing the CNR and lowering the noise. [ABSTRACT FROM AUTHOR]

Ventriculoperitoneal (VP) shunt placement, essential for managing hydrocephalus, often risks catheter malpositioning, especially in patients with small ventricles. We present a novel technique combining neuronavigation with intraoperative cone-beam computed tomography using the BrainLab system and Loop-X mobile imaging unit. This approach enables real-time verification of catheter placement by integrating preoperative MRI data with intraoperative CT imaging. In a 12-year-old boy with therapy-refractory idiopathic intracranial hypertension, neuronavigation was guided by the BrainLab Skull Fix and Cushing canula, ensuring precise catheter insertion into the right frontal horn. Post-placement, Loop-X facilitated immediate verification of the catheter's trajectory and positioning, corroborated by postoperative MRI. This technique demonstrated high precision and minimized radiation exposure, emphasizing its utility in reducing revision rates due to suboptimal catheter placement. [ABSTRACT FROM AUTHOR]

Background: Patients may undergo anatomical changes during radiotherapy, leading to an underdosing of the target or overdosing of the organs at risk (OARs). Purpose: This study developed a deep‐learning method to predict the tumor response of patients with nasopharyngeal carcinoma (NPC) during treatment. This method can predict the anatomical changes of a patient. Methods: The participants included 230 patients with NPC. The data included planning computed tomography (pCT) and routine cone‐beam CT (CBCT) images. The CBCT image quality was improved to the CT level using an advanced method. A long short‐term memory network‐generative adversarial network (LSTM‐GAN) is proposed, which can harness the forecasting ability of LSTM and the generation ability of GAN. Four models were trained to predict the anatomical changes that occurred in weeks 3–6 and named LSTM‐GAN‐week 3 to LSTM‐GAN‐week 6. The pCT and CBCT were used as input, and the tumor target volumes (TVs) and OARs were delineated on the predicted and real images (ground truth). Finally, the models were evaluated using contours and dosimetry parameters. Results: The proposed method predicted the anatomical changes, with a dice similarity coefficient above 0.94 and 0.90 for the TVs and surrounding OARs, respectively. The dosimetry parameters were close between the prediction and ground truth. The deviations in the prescription, minimum, and maximum doses of the tumor targets were below 0.5 Gy. For serial organs (brain stem and spinal cord), the deviations in the maximum dose were below 0.6 Gy. For parallel organs (bilateral parotid glands), the deviations in the mean dose were below 0.8 Gy. Conclusion: The proposed method can predict the tumor response to radiotherapy in the future such that adaptation can be scheduled on time. This study provides a proactive mechanism for planning adaptation, which can enable personalized treatment and save clinical time by anticipating and preparing for treatment strategy adjustments. [ABSTRACT FROM AUTHOR]

Background: The first commercially available photon‐counting‐detector CT (PCD‐CT) has been introduced for clinical use. However, its spectral performance on single‐ and dual‐contrast imaging tasks has not been comprehensively assessed. Purpose: To evaluate the spectral imaging performance of a clinical PCD‐CT system for single‐contrast material [iodine (I) or gadolinium (Gd)] and dual‐contrast materials (I and Gd) in comparison with a dual‐source dual‐energy CT (DS‐DECT). Methods: Iodine (5, 10, and 15 mg/mL) and gadolinium (3.3, 6.6, and 9.9 mg/mL) samples, and their mixtures (I/Gd: 5/3.3 and 10/6.6 mg/mL) were prepared and placed in two torso‐shaped water phantoms (lateral dimensions: 30 and 40 cm). These phantoms were scanned on a PCD‐CT (NAEOTOM Alpha, Siemens) at 90, 120, and 140 kV. The same phantoms were scanned on a DS‐DECT (SOMATOM Force, Siemens) with 70/Sn150, 80/Sn150, 90/Sn150, and 100/Sn150 kV. The radiation dose levels were matched [volume CT dose index (CTDIvol): 10 mGy for the 30 cm phantom and 20 mGy for the 40 cm phantom] across all tube voltage settings and between scanners. Two‐material decomposition (I/water or Gd/water) was performed on iodine or gadolinium samples, and three‐material decomposition (I/Gd/water) on both individual samples and mixtures. On each decomposed image, mean mass concentration (± standard deviation) was measured in circular region‐of‐interests placed on the contrast samples. Root‐mean‐square‐error (RMSE) values of iodine and gadolinium concentrations were reported based on the measurements across all contrast samples and repeated on 10 consecutive slices. Results: For all material decomposition tasks on the DS‐DECT, the kV pairs with greater spectral separation (70/Sn150 kV and 80/Sn150 kV) yielded lower RMSE values than other DS‐DECT and PCD‐CT alternatives. Specifically, for the optimal 70/Sn150 kV, RMSE values were 1.2 ± 0.1 mg/mL (I) for I/water material decomposition, 1.0 ± 0.1 mg/mL (Gd) for Gd/water material decomposition, and 4.5 ± 0.2 mg/mL (I) and 3.7 ± 0.2 mg/mL (Gd), respectively, for I/Gd/water material decomposition. On the PCD‐CT, the optimal tube voltages were 120 or 140 kV for I/water decomposition with RMSE values of 2.0 ± 0.1 mg/mL (I). For Gd/water decomposition on PCD‐CT, the optimal tube voltage was 140 kV with gadolinium RMSE values of 1.5 ± 0.1 mg/mL (Gd), with the 90 kV setting on PCD‐CT generating higher RMSE values for gadolinium concentration compared to all DS‐DECT and PCD‐CT alternatives. For three material decomposition, both imaging modalities demonstrated substantially higher RMSE values for iodine and gadolinium, with 90 kV being the optimal tube potential for Gd/I quantitation on PCD‐CT [5.4 ± 0.3 mg/mL (I) and 3.9 ± 0.2 mg/mL (Gd)], and DS‐DECT at 100/Sn150 kV having larger RMSE values for both materials compared to the alternatives for either modality. Conclusion: Optimal tube voltage for material decomposition on the clinical PCD‐CT is task‐dependent but inferior to DS‐DECT using 70/Sn150 kV or 80/Sn150 kV in two‐material decomposition for single‐contrast imaging (iodine/water or gadolinium/water). Three material decomposition (iodine/gadolinium/water) in dual‐contrast imaging yields substantially higher RMSE for both imaging platforms. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy of the prostate and the pelvic lymph nodes (LN) is a part of the standard of care treatment for high‐risk prostate cancer. The independent translational and rotational (i.e., six‐degrees‐of‐freedom, [6DoF]) motion of the prostate and LN target during and between fractions can perturb the dose distribution. However, no standard dose reconstruction method accounting for differential 6DoF target motion is available. Purpose: We present a framework for monitoring motion‐induced dose perturbations for two independently moving target volumes in 6DoF. The framework was used to determine the dose perturbation for the prostate and the LN target caused by differential 6DoF motion for a cohort of high‐risk prostate cancer patients. As a potential first step toward real‐time dose‐guided high‐risk prostate radiotherapy, we furthermore investigated if the dose reconstruction was fast enough for real‐time application for both targets. Methods: Twenty high‐risk prostate cancer patients were treated with 3‐arc volumetric modulated arc therapy (VMAT). Kilovoltage intrafraction monitoring (KIM) with triggered kilovoltage (kV) images acquired every 3 throughout 7–10 fractions per patient was used for retrospective 6DoF intrafraction prostate motion estimation. The 6DoF interfraction LN motion was determined from a pelvic bone match between the planning CT and a post‐treatment cone beam CT (CBCT). Using the retrospectively extracted motion, real‐time 6DoF motion‐including dose reconstruction was simulated using the in‐house developed software DoseTracker. A data stream with the 6DoF target positions and linac parameters was broadcasted at a 3‐Hz frequency to DoseTracker. In a continuous loop, DoseTracker calculated the target dose increments including the specified motion and, for comparison, without motion. The motion‐induced change in D99.5% for the prostate CTV (ΔD99.5%) and in D98% for the LN CTV (ΔD98%) was calculated using the final cumulative dose of each fraction and averaged over all imaged fractions. The real‐time reconstructed dose distribution of DoseTracker was benchmarked against a clinical treatment planning system (TPS) and it was investigated whether the calculation speed was fast enough to keep up with the incoming data stream. Results: Translational motion was largest in cranio‐caudal (CC) direction (prostate: [‐5.9, +8.4] mm; LN: [‐9.9; +11.0] mm) and anterior–posterior (AP) direction (prostate:[‐5.6; +6.9] mm; LN: [‐9.6; +11.0] mm). The pitch was the largest rotation (prostate: [‐22.5; +25.2] deg; LN: [‐3.9; +5.5] deg). The prostate CTV ΔD99.5% was [‐16.2; +2.5]% for single fractions and [‐3.0; +1.7]% when averaged over all imaged fractions. The LN CTV ΔD98% was [‐19.8; +1.2]% for single fractions and [‐3.1; +0.9]% after averaging. Mean (Standard deviation) absolute dose errors in DoseTracker of 107.8% (Std: 1.9%) for the prostate and 105.5% (Std:1.4%) for the LN were corrected during dose reconstruction by automatically calculated normalization factors. It resulted in accurate calculation of the motion‐induced dose errors with relative differences between DoseTracker and TPS dose calculations of ‐0.1% (Std: 0.5%) (prostate CTV ΔD99.5%) and ‐0.2% (Std: 0.5%) (LN CTV ΔD98%). The DoseTracker calculation was fast enough to keep up with the incoming inputs for all but two out of 107 184 dose calculations. Conclusion: Using the developed framework for dose perturbation monitoring, we found that the differential 6DoF target motion caused substantial dose perturbation for individual fractions, which largely averaged out after several fractions. The framework was shown to provide reliable dose calculations and a sufficiently high‐dose reconstruction speed to be applicable in real‐time. [ABSTRACT FROM AUTHOR]

Background: Although cone beam computed tomography (CBCT) has lower resolution compared to planning CTs (pCT), its lower dose, higher high‐contrast resolution, and shorter scanning time support its widespread use in clinical applications, especially in ensuring accurate patient positioning during the image‐guided radiation therapy (IGRT) process. Purpose: While CBCT is critical to IGRT, CBCT image quality can be compromised by severe stripe and scattering artifacts. Tumor movement secondary to respiratory motion also decreases CBCT resolution. In order to improve the image quality of CBCT, we propose a Lung Diffusion Model (L‐DM) framework. Methods: Our proposed algorithm is based on a conditional diffusion model trained on pCT and deformed CBCT (dCBCT) image pairs to synthesize lung CT images from dCBCT images and benefit CBCT‐based radiotherapy. dCBCT images were used as the constraint for the L‐DM. The image quality and Hounsfield unit (HU) values of the synthetic CTs (sCT) images generated by the proposed L‐DM were compared to three selected mainstream generation models. Results: We verified our model in both an institutional lung cancer dataset and a selected public dataset. Our L‐DM showed significant improvement in the four metrics of mean absolute error (MAE), peak signal‐to‐noise ratio (PSNR), normalized cross‐correlation (NCC), and structural similarity index measure (SSIM). In our institutional dataset, our proposed L‐DM decreased the MAE from 101.47 to 37.87 HU and increased the PSNR from 24.97 to 29.89 dB, the NCC from 0.81 to 0.97, and the SSIM from 0.80 to 0.93. In the public dataset, our proposed L‐DM decreased the MAE from 173.65 to 58.95 HU, while increasing the PSNR, NCC, and SSIM from 13.07 to 24.05 dB, 0.68 to 0.94, and 0.41 to 0.88, respectively. Conclusions: The proposed L‐DM significantly improved sCT image quality compared to the pre‐correction CBCT and three mainstream generative models. Our model can benefit CBCT‐based IGRT and other potential clinical applications as it increases the HU accuracy and decreases the artifacts from input CBCT images. [ABSTRACT FROM AUTHOR]

Innovation in image-guided procedures has been driven by advances in robotic Cone Beam Computed Tomography (CBCT) systems. A fundamental challenge for CBCT imaging is metal artifacts arising from surgical tools and implanted hardware. Here, we outline how two universal non-circular imaging orbits, optimized for metal artifact reduction, can be implemented in real-time on clinical robotic CBCT systems. Demonstrating potential clinical utility, the universal orbits were implemented during a pedicle screw cervical spine fixation and hip arthroplasty performed on a porcine and ovine cadaver respectively. In both procedures, the universal non-circular orbits noticeably reduced the metal artifacts surrounding the implanted orthopedic hardware, revealing anatomy and soft tissue obscured in current conventional CBCT imaging. This work represents a key step in clinically translating universal orbits, unlocking high quality in-room procedural verification to increase broader use of robotic CBCT systems and reduce the occurrence of secondary corrective surgeries. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Methods Results Conclusion The aim of this study was to evaluate root development in autotransplanted teeth using cone‐beam computed tomography (CBCT) images.Twelve premolars with incomplete root formation, which were selected to replace prematurely lost upper central incisors, were analyzed by CBCT on two different occasions. The first CBCT examination (T1) was conducted before tooth autotransplantation. The second CBCT examination (T2) was performed over a follow‐up period of at least 12 months and < 5 years. Three previously calibrated evaluators assessed root development. The positions of the tomographic planes were standardized. The mean root length in sagittal and coronal tomographic sections was used to validate the root length at T1 and T2. Longitudinal root development of the transplanted tooth was determined by calculating the difference in root length between T2 and T1. The intraclass correlation coefficient (ICC), paired t‐test, and Pearson test were applied, with significance set at 5%.The mean time elapsed between T1 and T2 was 962 days/2.6 years. The ICC was > 0.75. The measurements obtained at T2 were significantly greater than at T1 (p = 0.001). The mean increase in root length was 2.83 mm. There was no significant correlation (p = 0.413; r = 0.261) between root length increase and the time elapsed between T1 and T2.Premolar teeth with incompletely formed roots transplanted to the upper central incisor region showed continued root development during postoperative follow‐up. [ABSTRACT FROM AUTHOR]

Purpose: To provide detailed reports on radiation doses during transarterial chemoembolization (TACE) in the cone-beam computed tomography (CBCT) era and to identify the associated factors. Methods: This retrospective study included 385 consecutive patients who underwent initial conventional TACE for hepatocellular carcinoma (HCC) between January 2016 and December 2017. In most cases, CBCT was performed at the common hepatic artery or celiac axis to confirm the location of the tumor and the three-dimensional hepatic artery anatomy. Superselective TACE was performed for all technically feasible cases. Information on total dose area product (DAP), total cumulative air kerma (CAK), fluoroscopy time, and DAP and CAK of each digital subtraction angiography (DSA) and CBCT scan was recorded. Multiple linear regression analysis was performed to identify the factors associated with increased DAP during TACE. Results: The mean values of total DAP and CAK were 165.2 ± 81.2 (Gy·cm²) and 837.1 ± 571.0 (mGy), respectively. The mean fluoroscopy time was 19.1 ± 10.3 min. The mean DAP caused by fluoroscopy, DSA, and CBCT was 51.8 ± 43.9, 28.0 ± 24.1, and 83.9 ± 42.1 Gy·cm², respectively. Male sex, a high body mass index, largest tumor size > 3 cm, presence of aberrant right and left hepatic arteries, and superselective TACE were identified as independent predictors of increased total DAP during TACE. Conclusion: We were able to provide detailed reports on radiation doses during TACE and associated factors. [ABSTRACT FROM AUTHOR]

Background: Medical imaging segmentation is the use of image processing techniques to expand specific structures or areas in medical images. This technique is used to separate and display different textures or shapes in an image. The aim of this study is to develop a deep learning-based method to perform maxillary sinus segmentation using cone beam computed tomography (CBCT) images. The proposed segmentation method aims to provide better image guidance to surgeons and specialists by determining the boundaries of the maxillary sinus cavities. In this way, more accurate diagnoses can be made and surgical interventions can be performed more successfully. Methods: In the study, axial CBCT images of 100 patients (200 maxillary sinuses) were used. These images were marked to identify the maxillary sinus walls. The marked regions are masked for use in the maxillary sinus segmentation model. U-Net, one of the deep learning methods, was used for segmentation. The training process was carried out for 10 epochs and 100 iterations per epoch. The epoch and iteration numbers in which the model showed maximum success were determined using the early stopping method. Results: After the segmentation operations performed with the U-Net model trained using CBCT images, both visual and numerical results were obtained. In order to measure the performance of the U-Net model, IoU (Intersection over Union) and F1 Score metrics were used. As a result of the tests of the model, the IoU value was found to be 0.9275 and the F1 Score value was 0.9784. Conclusion: The U-Net model has shown high success in maxillary sinus segmentation. In this way, fast and highly accurate evaluations are possible, saving time by reducing the workload of clinicians and eliminating subjective errors. [ABSTRACT FROM AUTHOR]

Investigation of the biological sex of human remains is a crucial aspect of physical anthropology. However, due to varying states of skeletal preservation, multiple approaches and structures of interest need to be explored. This research aims to investigate the potential use of distances between bifrontal breadth (FMB), infraorbital foramina distance (IOD), nasal breadth (NLB), inter-canine width (ICD), and distance between mental foramina (MFD) for combined sex prediction through traditional statistical methods and through open-access machine-learning tools. Ethical approval was obtained from the ethics committee, and out of 100 cone beam computed tomography (CBCT) scans, 54 individuals were selected with all the points visible. Ten extra exams were chosen to test the predictors developed from the learning sample. Descriptive analysis of measurements, standard deviation, and standard error were obtained. T-student and Mann–Whitney tests were utilized to assess the sex differences within the variables. A logistic regression equation was developed and tested for the investigation of the biological sex as well as decision trees, random forest, and artificial neural networks machine-learning models. The results indicate a strong correlation between the measurements and the sex of individuals. When combined, the measurements were able to predict sex using a regression formula or machine learning based models which can be exported and added to software or webpages. Considering the methods, the estimations showed an accuracy rate superior to 80% for males and 82% for females. All skulls in the test sample were accurately predicted by both statistical and machine-learning models. This exploratory study successfully established a correlation between facial measurements and the sex of individuals, validating the prediction potential of machine learning, augmenting the investigative tools available to experts with a high differentiation potential. [ABSTRACT FROM AUTHOR]

Adjuvant radiation therapy (ART) after radical cystectomy in locally advanced bladder cancer was revived after the advancement in precise radiation therapy that decreased the normal pelvic tissue radiation hazards. However, there are still scarce controlled randomized studies addressing this issue. One hundred thirty-one cystectomized urothelial bladder cancer patients were enrolled; 122 were randomized to receive ART of 50 Gy/25 fractions 4 weeks after cystectomy or cystectomy alone (CY). Sixty-two were included in the ART arm and 60 in the CY arm. Twenty-four ART and 30 CY patients received neoadjuvant chemotherapy. Eleven patients (9%) had cotenant neobladder diversion, 6 in ART, and 5 in CY arms. All ART patients were treated with intensity modulated radiation therapy with daily verification cone beam computed tomography. The median follow-up was 42.7 months. The 3-year adjusted locoregional recurrence–free survival rate was higher in the ART arm, measuring 81% (95% CI, 69%-94%) compared with 71% (95% CI, 60%-80%; p =.0457). ART significantly improved the locoregional relapse–free rate in the cystectomy bed and the pelvic side wall (p =.016 and p =.001, respectively). The overall, event-free, and distant metastasis–free survival did not rank to the level of statistical significance in the 2 arms. Even though the acute side effects were slightly higher in ART, the late toxicities were almost equal in the 2 groups. ART is safe and quite tolerable after radical cystectomy when using precise radiation techniques. These techniques significantly improved the locoregional recurrence–free survival but had insignificant improvement on the overall survival. ART did not affect the distant metastasis–free survival. Similar studies are performed in different centers around the world to confirm the value of ART in urothelial bladder cancer. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to compare student learning of cone beam computed tomography (CBCT) interpretation using immersive virtual reality (VR) and three‐dimensional multiplanar (MP) reconstructions. Methods: Sixty first‐year dental students were randomly allocated to two groups, VR and MP, and underwent a one‐on‐one educational intervention to identify anatomic structures using CBCT data. All participants completed three multiple‐choice questionnaires (MCQs) before (T1), immediately after (T2), and 2 weeks following (T3) the intervention. Additionally, pre‐survey, post‐survey, NASA Task Load Index (NASA‐TLX), and presence questionnaires were completed. Analysis of objective measures of performance on MCQs and subjective data from the questionnaires was completed (α = 0.05). Results: There was a significant increase in test performance and informational recall between T1–T2 and T1–T3 for VR and MP groups (p < 0.001). However, there were no significant differences in performance on MCQs between T2 and T3. Analysis of the Presence questionnaire indicated that the VR group felt decreased distraction (p = 0.013), increased realism (p = 0.035), and increased involvement (p = 0.047) during the educational intervention when compared with the MP group. Analysis of the NASA‐TLX indicated that the VR group experienced more physical demand (p < 0.01) but similar cognitive demand when compared with the MP group. Qualitative responses indicated that the VR group had a more dynamic sense of visualization and manipulation compared to the MP group. Conclusion: Results from this study show that VR is as effective as traditional MP methods of CBCT interpretation learning. Further benefits of VR educational intervention include increased involvement, realism and less distraction. [ABSTRACT FROM AUTHOR]

The "Journal of Veterinary Dentistry" contains abstracts from various studies related to veterinary dentistry. Studies include topics such as the use of videoscopes in periodontal surgery, the effects of stannous fluoride dentifrice on oral health, the relationship between periodontitis and systemic diseases, and the use of stem cells in regenerative endodontics. Other studies explore the properties of bioactive ceramic cements, the mobility of the mandibular symphysis in cats, and the anatomy of pulp cavities in feline teeth. Additionally, studies examine the outcomes of root canal treatments in fractured teeth, the prevalence of dentigerous cysts in dogs, and the impact of communication strategies on dog owners' adherence to dental care recommendations. [Extracted from the article]

A 6-month-old intact male Dalmatian mix puppy was presented for the evaluation of left maxillary swelling due to a suspected cyst and an unerupted left maxillary canine tooth. Removal of the unerupted left maxillary canine tooth (204) and enucleation of the cyst was performed, followed by histological analysis, which identified the maxillary swelling to be a cystic ameloblastic fibroma. Ameloblastic fibromas are rare in companion animals, and to the best of the authors' knowledge, this is the first cystic variant reported in dogs. The clinical, radiographic, cone beam computed tomography, and histological findings of this case are discussed and compared with the findings of previously documented human and domestic animal cases. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between roll rotation of the jaws and changes in alar base or lip line asymmetry in the coronal plane following orthognathic correction. The study involved patients with preoperative frontal alar base and lip line asymmetries greater than 0.5° (because it corresponds to the minimum asymmetry perception threshold) and underwent bimaxillary orthognathic surgery without (Group I) or with (Group II) genioplasty. The alar base angle (ABA), lip line cant angle (LLCA), maxillary cant angle (MxCA), and mandibular cant angle (MnCA) were measured using preoperative and 12 months postoperative cone beam computed tomography (CBCT) images. Thirty-four patients were included in the study. Significant correlations were found between changes in MxCA and ABA besides between changes in MnCA and LCA in Groups I (P = 0.016, P ˂0.001, respectively) and II (P = 0.002, P ˂0.001, respectively). The mean of the change in ABA/the change in MxCA and the change in LLCA/the change in MnCA ratios for Group I were 0.59 ± 1.57 and 0.73 ± 0.94, respectively, while those for Group II were 0.46 ± 3.70 and 0.39 ± 2.00, respectively. Angular measurements from jugular and mental foramina points, aligned with the bony midline, offer a convenient tool for predicting alar base and lip symmetry during bimaxillary orthognathic surgery planning. [ABSTRACT FROM AUTHOR]

The optic nerve canal (ONC) is a fine skeletal structure that contains the optic nerve. However, it has not been thoroughly examined. This necessitates establishing a baseline knowledge of the geometrical and volumetric parameters of the ONC. The data of twenty patients who received a cone beam computed tomography examination were prepared using a voxel-based segmentation. The measurement was performed separately by two examiners on virtual skull models in stereolithography format in Geomagic Wrap®. The results showed that the volume of the ONC varied between 92.48 mm3 and 162.7 mm3 (M = 123.46 mm3, SD = 26.61 mm3). Sex-specific statistically significant differences in volume were detected only for the right side. The angle of the ONC to the skull base was independent of the diameter of the canal. Both the intrarater and interrater comparisons of the measurements showed high values of reproducibility of the results. This study showed that a virtual anatomical model provides a feasible and reliable method to investigate the ONC. The examination technique could have a wider range of application in anthropology and application in clinical medicine. Advances in the automation of radiological diagnostics and the digital analysis of X-ray images could help to reduce examination times. [ABSTRACT FROM AUTHOR]

Objective: To assess the association between three-dimensional inclination of the osseous structures of temporomandibular joints (TMJ) and the risk of disc displacement (DD). Methods: The 120 TMJs of 60 patients were evaluated. According to magnetic resonance images, disc position was classified as normal, anterior DD with reduction (ADDWR) and without reduction (ADDWoR) and as normal, medial DD (MDD), and lateral DD (LDD) on the sagittal and coronal views, respectively. Condyle and eminence inclinations were measured using cone beam computed tomography. Results: Smaller horizontal condylar inclination was associated with ADDWoR (p < 0.05). Larger coronal condylar inclination was associated with ADDWR (p < 0.05) and LDD (p < 0.05). There was no association between sagittal eminence inclination and DD (p < 0.05). Conclusion: Medial condylar rotation in the axial view may be associated with ADDWoR. The condyle head horizontally inclined in the coronal view may be associated with ADDWR and LDD. [ABSTRACT FROM AUTHOR]